What is a thoracic aortic aneurysm?
A thoracic aortic aneurysm, also called TAA, is a bulging, weakened area in the wall of the aorta (the largest artery in the body), resulting in an abnormal widening or ballooning greater than 50 percent of the normal diameter (width).
The aorta extends upward from the top of the left ventricle of the heart in the chest area (ascending thoracic aorta), then curves like a candy cane (aortic arch) downward through the chest area (descending thoracic aorta) into the abdomen (abdominal aorta). The aorta delivers oxygenated blood pumped from the heart to the rest of the body.
An aneurysm can be characterized by its location, shape, and cause. A thoracic aortic aneurysm is located in the chest area. The thoracic aorta can be divided into segments: ascending aorta, aortic arch, and descending aorta, as described above. An aneurysm may be located in one of these areas and/or may be continuous throughout the aorta. An aneurysm called a thoracoabdominal aneurysm involves a thoracic aortic aneurysm extending down to the abdominal aorta.
Thoracic aneurysms do not occur as often as abdominal aneurysms. The descending thoracic aorta is the most common location of a thoracic aneurysm, followed by the ascending segment, then the arch. The location of an aneurysm is distinctly connected with the cause, course, and treatment of a thoracic aneurysm.
What causes a thoracic aortic aneurysm to form?
Thoracic aortic aneurysms may be caused by different disease processes, especially in respect to their location.
Examples of different locations of thoracic aortic aneurysms and their causes may include, but are not limited to, the following:
Location of Thoracic Aortic Aneurysm
Causes Associated with Aneurysm Type
Ascending Thoracic Aneurysm
cystic medial degeneration (necrosis) – breaking down of the tissue of the aortic wall. This is the most common cause of this type of thoracic aortic aneurysm.
genetic disorders which affect the connective tissue, such as Marfan syndrome and Ehlers-Danlos syndrome
family history of thoracic aortic aneurysm with no incidence of Marfan syndrome
atherosclerosis – hardening of the arteries caused by a build-up of plaque in the inner lining of an artery. This is a rare cause of ascending thoracic aortic aneurysm.
infection, syphilis (rare causes of thoracic aortic aneurysm)
Aortic Arch Thoracic Aneurysm
Descending Thoracic Aortic Aneurysm
Atherosclerosis is most often associated with descending thoracic aneurysms, and is thought to play an important role in aneurysmal disease, including the risk factors associated with atherosclerosis such as:
age (greater than 55)
family history (first-degree relatives such as father or brother)
hyperlipidemia (elevated fats in the blood)
hypertension (high blood pressure)
Treatment for thoracic aortic aneurysm:
Specific treatment will be determined by your physician based on:
• your age, overall health, and medical history
• extent of the disease
• your signs and symptoms
• your tolerance for specific medications, procedures, or therapies
• expectations for the course of the disease
• your opinion or preference